intercalated cell

Renal oncocytoma is thought to arise from the intercalated cells of collecting ducts of the kidney.

For their contribution to acid-base homeostasis, the intercalated cells play important roles in the kidney's response to acidosis and alkalosis.

Each component of the collecting duct system contains two cell types, intercalated cells and a segment-specific cell type:

Intercalated cells come in α and β varieties and participate in acid-base homeostasis.

In the intercalated cells of the kidney, V-ATPases pump protons into the urine, allowing for bicarbonate reabsorption into the blood.

Aldosterone also acts on intercalated cells to stimulate an apical proton ATPase, acidifying urine and alkalizing extracellular fluid.

The distal intercalated cells function normally, so the acidemia is less severe than dRTA and the urine can acidify to a pH of less than 5.3.

Distal RTA is characterized by a failure of acid secretion by the alpha intercalated cells of the cortical collecting duct of the distal nephron.

The acidosis is variable, and one may have dRTA with alpha intercalated cell failure without necessarily being acidemic; this is termed incomplete dRTA.

This leads to the clinical features of dRTA; In other words, the intercalated cells' apical H+/K+ antiporter is non-functional, resulting in potassium-wasting and proton retention.

Aldosterone stimulates secretion of H in exchange for Na in the intercalated cells of the cortical collecting tubules, regulating plasma bicarbonate (HCO) levels and its acid/base balance.

Hereditary causes include mutations of Band 3 the basolateral bicarbonate transporter of the intercalated cell, which may be transmitted in an autosomal dominant fashion in western European cases, or in an autosomal recessive fashion in South East Asian cases.

Aldosterone's effects are on the distal convoluted tubule and collecting duct of the kidney where it causes increased reabsorption of sodium and increased excretion of both potassium (by principal cells) and hydrogen ions (by intercalated cells of the collecting duct).